The present invention relates to a device and a method for welding and separating packaging materials for a package, having a combined ultrasonic welding device and cutting device which is used, in particular, in bag forming, filling and sealing machines.
Bag forming, filling and sealing machines, which pack sweets and other articles, are known in the prior art. In this context, a longitudinally closed tube, the one open end of which is sealed by a transverse sealing seam by means of an ultrasonic welding device comprising a sonotrode and an anvil, is usually produced from a film via a forming shoulder. Here, the packaging material is welded between the sonotrode and the anvil by touching of the two parts. After filling, the tube is then closed over the filling region by a further transverse sealing seam to form a tubular bag. In addition, bladed cutting devices are usually provided in order to separate the still joined bags. Due to contacts of the blade with the sonotrode, wear phenomena are obtained, so that the blades must be replaced, after a certain period of use. From WO 2008/102250, for example, it is also known that special hard metal inserts are used in the ultrasonic tools in order to reduce the contact-induced wear.